Revisit the Pitot static tubes in the standards

A Pitot tube is a popular device used for the measurements of flow fields. To control the accuracy of the Pitot tube coefficient, the international standard organization (ISO), the American Society for Testing and Materials (ASTM), and the Japanese Industrial Standards (JIS) issued guidelines that recommended the shape and working conditions of these devices. However, many Pitot tubes on the market do not follow these guidelines. In the present study, various types of Pitot tubes in the market were tested at the National Metrology Institute of Japan (NMIJ) to determine the effects of the geometry and flow characteristics. The results revealed certain limitations in the existing ISO and JIS standards, specifically with regard to the recommended design parameters of the AMCA Pitot tube, the reference coefficient value for the JIS Pitot tube, and the redefinition and limitation of Reynolds numbers pertaining to Pitot tube working conditions. [Display omitted] •The present work aims to survey the geometry and performance of Pitot tubes fabricated with different manufacturers and determine the effects of the flow characteristics on their performance outcomes.•Thirteen Pitot tubes consisted of four tubes of the NPL type, three tubes of the AMCA type, three tubes of the CETIAT type, and three tubes of the JIS type were selected for testing. None of the AMCA tubes' geometry follows the ASTM or ISO 3966 guideline. The CETIAT type could not find in the market. Accordingly, three CETIAT-type tubes were procured via special order in Japan.•The effects of the flow characteristics on all of the Pitot tubes' coefficients were tested in NMIJ standard air speed systems. These systems consist of a medium wind tunnel (MWT) and a high air speed system (HASS).•At velocities from 5 m/s to 90 m/s, the AMCA type of Pitot tube has coefficients that are more stable and homologous than other types. However, they have shape dimensions that differ from the recommendation in ISO 3699.•The surface roughness affects Pitot tube performance outcomes. Moreover, simplification of the CETIAT Pitot tube initially gives a good pressure response. The performance of Pitot tubes is stable at Red > 600, but as Red